6MoN: IPv4/IPv6 address utilization network monitoring tool

The IANA pool of available IPv4 address space was exhausted on February 1st, 2011. It is foreseen that during the end of the year 2011 APNIC will exhaust the available IPv4 address space. From that moment on, it is foreseen that more Regional Internet Registries will progressively exhaust their IPv4 address pool and start assigning only IPv6 addresses. In this scenario, there will be IPv4 networks, IPv6 networks and dual-stack (networks implementing both protocols). The transition from IPv4 to IPv6 does not require an upgrade on all hosts of the network at the same time but it can be implemented gradually. The transition period will be a long process of coexistence, probably decades, of both protocols until gradually the whole Internet will be IPv6 capable. There are many transition mechanisms al- lowing smooth integration of IPv4 and IPv6 networks, such as dual-stack, tunnels and NAT. The CNR Research Area of Pisa is connected to the Internet through the Italian National Research and Education Network { GARR, using both na- tive IPv6 and IPv4 protocol networks. Almost all hosts and the network equipments are dual stack having both ocial IPv4 and IPv6 addresses. At the research area of Pisa global unicast IPv6 addresses can be assigned using static, DHCPv6 or Stateless address auto-con guration (SLAAC). In case of network failure and troubleshooting, a network administrator may have interest to identify the owner of an IPv6 address to solve prob- lems that may be challenging. The aim of this technical report is to present a network monitoring software that allows a network administrator to iden- tify an IPv6 node in an easy manner by simply listening to broadcast and multicast packets in a passive mode, which makes the monitoring tool independent of any rewalls installed on hosts. The software has been developed by GruppoReti of the Institute of Informatics and Telematics of CNR. The tool is distributed to the research community for free; it is available on the project home page as VMware image at http://servizirete.pi.cnr.it/. It has been used for several months in Pisa. The number of institutions using the tool are continuously increasing. The tool relies on several network protocols for its operation such as ARP, NDP, Radius, 802.1x.